Cervical Spondylomyelopathy: Wobbler

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Cervical Spondylomyelopathy Wobbler

• Cervical spinal cord compression (C5-C7) as a
  result of caudal vertebral malformation or
  misarticulation.
• Large breed dogs (Great danes and Dobermans)
• Signs
• Progressive hind-limb ataxia (wobbly gait)
• Pelvic limbs cross each other when walking
• Abduct widely/tend to collapse
• May drag toes (wears dorsal surface of nails)
• Impaired proprioception
• Signs may also be present in front limb
• Crouching stance with downward flexed neck
• Rigid flexion of neck may have neck pain

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Cervical Spondylomyelopathy Wobbler

• Dx
• Radiographs to show malalignment and narrowing of
  spinal canal
• Myelogram is essential to locate the region of
  compression
• CT and MRI if available

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Cervical Spondylomyelopathy
MYELOGRAM C6-C7
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Cervical Spondylomyelopathy Wobbler

• Rxwithout treatment, prognosis is poor
• Medical
• Anti-inflammatory doses of corticosteroids
• Neck brace
• Cage confinement
• Surgical
• Decompression of spinal cord by laminectomy
• Stabilize vertebral column
• screws and wire dorsally
• spinal fusion ventrally

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Cervical Spondylomyelopathy Wobbler

• Client info
• Prognosis is guarded
• Most likely a hereditary disease
• Multiple levels of compression less favorable
  prognosis than a single area of compression
• Surgery is risky and costly

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Degenerative Myelopathy

• Etiologyunclear
• May be autoimmune response to antigen in nerv sys
• Degeneration of white matter in ascending and
  descending tracts
• Multiple sclerosis - humans
• Signs
• Mainly in G Shep and Shep mixes (gt5 yr)
• Progressive ataxia and paresis of hind limbs
  (5-6 months)
• Loss of proprioception is first sign
• Dog falls down when trying to defecate
• Muscle wasting of back muscles along caudal
  thoracic and lumbosacral areas
• Symptoms progress until animal is unable to
  support weight on hind limbs

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Degenerative Myelopathy

• Dx
• Neurologic Exam
• ? proprioception
• ? patellar reflexes
• Lack of pain
• Normal sphincter tone normal panniculus
• (pin prick) reflex
• Radiographs usually normal
• Rxnone symptoms will progress to
• paralysis
• Client info
• Degenerative myelopathy is a progressive,
  incurable disease
• Although symptoms are similar at early stages, it
  is a different disease from hip dysplasia
• When dog cannot support weight, quality of life
  should be evaluated

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Degenerative Myelopathy
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PERIPHERAL NERVOUS SYSTEM
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Deafness

• 1) Damage to auditory pathway
• chronic otitis
• rupture of tympanic membrane
• damage to middle ear (ossicles)
• 2) Damage to
• auditory nerve

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Deafness

• 3) Hereditary or congenital
• Bull terriers, Dobes, Rotts, Pointers, blue-eyed
  white cats, Dalmations, Aust Heelers, Aust
  shepherds, Eng setters, Catahoula
• 4) Related to drug therapy
• Amimoglycosides
• (gentamicin, streptomycin, kanamycin
• Topical polymyxin B
• Chloramphenicol
• Chlorhexidine w/ centrimide
• 5) Normal old ageusually due to atrophy of nerve
  ganglia or cochlear hair cells (also loud rock
  music)

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Deafness

• Dx
• Inability to rouse sleeping animal with loud
• noise (e,g,. blast from air horn) is diagnostic
• RxNo treatment is available in most cases
• Hearing aids are available for animals,
• but most will not tolerate something in ear
  canal
• Client info
• Hearing loss is permanent
• If hereditary, do not breed
• Animals can be taught to hand signals rather than
  words
• Animals should not be off leash when outside
• Hearing aids are available for dogs but are
  usually not tolerated would only be appropriate
  for hearing impaired

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Laryngeal Paralysis

• 3 typesalways be cautious of
• laryngeal paralysis because of the
• chance of rabies
• Hereditaryseen in Bouvier des Flandres and
  Siberian Huskies
• Seen at 4-6 mo of age
• Acquiredcan occur from lead poisoning, rabies,
  trauma, inflammation of vagus nerve
• 1.5 to 13 yr of age
• Idiopathicseen in middle-age to old large- and
  giant-breed dogs castrated dogs and cats have a
  higher incidence than female and non-neutered
  males

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Laryngeal Paralysis

• Signs
• Inspiratory stridor
• Resp distress
• Loss of endurance
• Voice change
• Dyspnea/cyanosis/complete resp collapse
• Dxlaryngoscopy will show laryngeal abductor m.
  (away from midline) dysfunction
• Rxsurgical intervention including
• Arytenoidectomy
• Removal of vocal folds
• Client infoprognosis is guarded to good do not
  breed if hereditary

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Laryngeal Paralysis
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Megaesophagus

• Causes-lack of esophageal peristalsis (3 types)
• Hereditarya gene for the disease is identified
  in wire-haired fox terriers and min schnauzers
• CongenitalG Danes, G Shepherd, I Set, Newfound,
  Shar-Peis, greyhounds (no gene IDed)
• evident about weaning time when solid food is
  introduced
• Due to incomplete nerve development in esophagus
• Acquiredmay be seen at any age Pb tox may be
  associated with neuropathies (e.g., myasthenia
  gravis, tick paralysis)
• Signs
• Regurgitation of undigested food
• Respiratory problems (aspiration pneumonia)
• Lack of growth

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Megaesophagus
Dxbarium swallow
Esophagus is 3 times normal diameter
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Megaesophagus

• Rx
• Elevated feeding (on platform, stairs)
• Liquid or soft diet high in calories
• Give several small feedings daily
• Gastrostomy tube (long term) is an option
• Client info
• Prognosisguarded to poor
• Treatment aim is to reduce clinical signs and
  prevent aspiration pneumonia
• There is no cure

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Tick Paralysis

• Causefemale tick (Dermacenter variablis, D.
  andersoni) ? salivary neurotoxin
• Neurotoxin interfered with Ach at neuromuscular
  jct
• Not seen in cats humans are affected
• Signs
• Gradual onset of voice changes and hind-limb
  ataxia (motor deficit) progressing to a flaccid,
  ascending paralysis (1-3 d)
• Sensation is intact
• Ticks on the dog
• Rx
• Remove ticks (manually or with dip)
• Usually resolves in 1-3 d
• Supportive care until dog recovers
• Ventilation required for resp paralysis

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Tick Paralysis
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Coonhound Paralysis (Polyradiculoneuritis )

• -thought to be an immune response to an unknown
  etiologic factor in raccoon saliva
• -some dogs will get it 1-2 wk after exposure,
  others exposed to same raccoon will not
• Signs(similar to tick paralysis and rabies)
• Weakness begins in hind limbs with paralysis
  progressing rapidly to a flaccid tetraplegia
• Alert, afebrile animal
• Loss of spinal reflexes (patella tap, etc)
• Loss of voice labored breathing inability to
• lift head
• May die of resp failure
• May last for 2-3 mo (usually good Px)
• Rxsupportive nursing care
• Client info
• Dogs can be affected without exposure to raccoon
• May require long-term nursing care
• Some animals will regain total function, while
  more severely affected animals may not

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Idiopathic Facial Nerve Paralysis

• Etiologyunknown
• Occurrence
• C Span, Corgis, Boxers, E Set, DLH cats
• Signs
• Older dogs (gt5 y)
• Ear droop
• Lip paralysis
• Sialosis (drooling)
• Deviation of nose
• Collection of food in paralyzed side of mouth
• Absence of menace and palpebral reflex

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Idiopathic Facial Nerve Paralysis

• Rxefficacy of corticosteroids unknown
• Artificial tears to prevent corneal ulcers
• Keep oral cavity clear of food
• Client info
• Cause is unknown
• Complete recovery does not usually occur
• May develop keratoconjunctivitis sicca (dry eye)
• Animals may require life-long maintenance